A conventional solid electrolytic capacitor includes capacitor elements. Each capacitor element includes an electrode portion which is a core at one side or a center in the thickness direction of a porous valve metal sheet, such as aluminum or tantalum, a dielectric layer formed on a porous surface of the valve metal sheet, a solid electrolyte layer made of e.g. functional high polymer, provided on the dielectric layer, a collector layer provided on solid electrolyte layer, and an electrode layer of metal on the collector layer. The solid electrolytic capacitor elements are stacked. Respective electrode portions of the solid electrolytic capacitor elements are connected to an external terminal, and respective electrode layers of the capacitor elements are connected to another external terminal. A package is provided so that the external terminals may be exposed outside of the package.
The conventional solid electrolytic capacitor can have a large capacitance and a small equivalent series resistance (ESR), but must be mounted on a circuit board through the external terminals similarly to a general solid electrolytic capacitor.
The solid electrolytic capacitor mounted on a circuit board like a semiconductor device has a large ESR and a large equivalent series inductance (ESL) due to lengths of the terminals or wires, thus having an inferior radio frequency response.
To solve such problems, a solid electrolytic capacitor capable having a small ESR and ESL is proposed. Both positive and negative electrodes are disposed on one side of the solid electrolytic capacitor, and electronic components are directly mounted on the solid electrolytic capacitor.